object.c: fix exponent with underscore

* object.c (rb_cstr_to_dbl_raise): do not ignore exponent part
  when the input string longer than internal buffer contains
  underscore(s).  [ruby-core:86836] [Bug #14731]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63322 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 5 insertions, 1 deletions

diff --git a/object.c b/object.c
index 4a5b5d359a..a4594a2982 100644
--- a/object.c
+++ b/object.c
@@ -3270,7 +3270,8 @@ rb_cstr_to_dbl_raise(const char *p, int badcheck, int raise, int *error)
     if (*end) {
         char buf[DBL_DIG * 4 + 10];
         char *n = buf;
-        char *e = buf + sizeof(buf) - 1;
+        char *const init_e = buf + DBL_DIG * 4;
+        char *e = init_e;
         char prev = 0;
 
         while (p < end && n < e) prev = *n++ = *p++;
@@ -3283,6 +3284,9 @@ rb_cstr_to_dbl_raise(const char *p, int badcheck, int raise, int *error)
                 }
             }
             prev = *p++;
+            if (e == init_e && (*p == 'e' || *p == 'E')) {
+                e = buf + sizeof(buf) - 1;
+            }
             if (n < e) *n++ = prev;
         }
         *n = '\0';